This invention relates to a batching machine for dyes or pigments in the liquid state. These machines are already known as a result of prior patents filed by the same applicant.
The said machines basically comprise an assembly consisting of a number of liquid pigment tanks or containers known as canisters, each of which is fitted with systems designed to mix the dye continuously inside the canister, a measuring device to regulate the amount of pigment dispensed, and a dispensing nozzle.
In view of the fact that these machines have to produce dyes of numerous different shades, it is necessary to have a relatively large number of basic colours and therefore canisters.
In order to limit the size of the machine, the said canisters are preferably wedge or crescent shaped, and are arranged radially around a dispensing area; the outlet nozzles of the canister are directed towards the dispensing area, and the receptacles to be filled are placed under it.
In particular, a first known technique involves directing the dispensing nozzles in a roughly vertical manner towards the dispensing area.
In batching machines so designed, the dispensing openings are situated along a circumference, and as their number is relatively large, the pigments are dispensed over a relatively large diameter.
For example, if there are 16 canisters, the dispensing openings are situated on a circumference with a diameter of at least 50 mm.
In view of these factors, the main drawback of this first known technique is obviously the fact that it is impossible to pour the pigments into collector jars or containers with a mouth of a smaller diameter than the one on which the dispensing openings are situated.
A second known technique involves connecting the outlets of each canister by means of a pipe or the like to a dispensing head comprising the same number of channels as the number of canisters, the said channels leading to outlet openings located on concentric circumferences.
This system considerably reduces the diameter of the pigment dispensing area.
For example, if there are 16 canisters, the dispensing diameter will be reduced to approx. 25 mm.
However, although this second known technique is popular because it allows even collector vessels with mouths of a small diameter to be employed with a large number of canisters, it still presents a number of drawbacks.
As there is very little free space, it is extremely difficult to connect the canister outlets to the dispensing head after the canisters have been fitted into their housings.
As a result, the canisters have to be connected to the dispensing head with hoses before being fitted in their final position.
The use of these hoses, which are much longer than theoretically necessary, causes considerable inconvenience.
When the dye remains motionless in the hoses, sedimentation takes place; in time the sediment tends to block the hoses, and therefore prejudice the normal operation of the machine.
The fact that the hoses have to be fixed to the canisters and the dispensing head also makes the fitting and removal of the canisters more laborious.
This is particularly inconvenient, and makes dismantling and reassembly of the machine very difficult and laborious, especially when the canisters are removed for maintenance operations.